1. Field of the Invention
The present invention relates to a disc recliner for a seat assembly of an automotive vehicle that allows pivotal adjustment of a seat back relative to a seat cushion. More particularly, the present invention relates to a continuous disc recliner having a release feature to quickly adjust a seat back to an easy-entry position or a fold flat position.
2. Description of Related Art
Automotive vehicles typically include one or more seat assemblies having a seat cushion and a seat back for supporting a passenger above a vehicle floor. The seat assembly is commonly mounted to the vehicle floor by a seat track assembly for providing fore and aft adjustment of the seat assembly for passenger comfort. The seat back is typically operatively coupled to the seat cushion by a recliner assembly for providing selective pivotal adjustment of the seat back relative to the seat cushion.
One well known type of recliner assembly includes a pair of continuous disc recliners to operatively couple the seat back to the seat cushion. A typical prior art continuous disc recliner as illustrated in U.S. Patent Application Publication No. 2012/0001471 includes a fixed plate secured to the seat cushion and a movable plate secured to the seat back and rotatably coupled to the fixed plate. The fixed plate is formed to include an outer profile having a plurality of outwardly-facing teeth and the movable plate is formed to include an inner profile having a plurality of inwardly-facing teeth. The tooth count of the outwardly-facing teeth is at least one less tooth than the tooth count of the inwardly-facing teeth. A drive mechanism is disposed between the movable plate and the fixed plate and is operable for urging the movable plate to rotate relative to the fixed plate. The drive mechanism includes a cam and a pair of wedges that define an eccentric element, which presses the outwardly-facing teeth on the fixed plate into the inwardly-facing teeth on the movable plate at an engagement point defined by the eccentricity of the eccentric element. When the cam is rotated in a first direction, the wedges are driven in the first direction causing the direction of the eccentricity to shift, thereby shifting the engagement point of the outwardly-facing teeth and the inwardly-facing teeth. The shifting of the engagement point manifests itself as a wobbling rotational movement of the movable plate in the first direction, thereby reclining the seat back. When the cam is rotated in a second direction, the wedges are driven in the second direction causing the direction of the eccentricity to shift, thereby shifting the engagement point of the outwardly-facing teeth and the inwardly-facing teeth. The shifting of the engagement point manifests itself as a wobbling rotational movement of the movable plate in the second direction, thereby raising the seat back. The seat back is maintained in a desired seating position due to friction between the outwardly-facing teeth and the inwardly-facing teeth at the engagement point as well as friction between the wedges and the fixed and movable plates.
One drawback of continuous disc recliners is the inability of providing quick adjustment or “dumping” of the seat back through a large seat back angle to an easy-entry position or a fold flat position overlying the seat cushion. In order to pivot the seat back to the easy-entry position or the fold flat position, continuous disc recliners must be actuated through the entire range of adjustment. While this offers very good fine adjustment of the seat back, the longer actuation time to move the seat back through the large seat back angle is undesirable.
It is desirable therefore to provide a continuous disc recliner having an improved release feature to quickly adjust a seat back to an easy-entry position or a fold flat position.